Preparation

Make the crust:
In a bowl combine the cracker crumbs, the pecans, and the sugars, stir in the butter, and press the mixture into the bottom and 1/2 inch up the side of a buttered 9-inch springform pan. Chill the crust for 1 hour.

Make the filling:
In a bowl whisk together the pumpkin, the egg, the cinnamon, the nutmeg, the ginger, the salt, and the brown sugar. In a large bowl with an electric mixer cream together the cream cheese and the granulated sugar, beat in the cream, the cornstarch, the vanilla, the bourbon liqueur, and the pumpkin mixture, and beat the filling until it is smooth.

Pour the filling into the crust, bake the cheesecake in the middle of a preheated 350°F. oven for 50 to 55 minutes, or until the center is just set, and let it cool in the pan on a rack for 5 minutes.

Make the topping:
In a bowl whisk together the sour cream, the sugar, and the bourbon liqueur.

Spread the sour cream mixture over the top of the cheesecake and bake the cheesecake for 5 minutes more. Let the cheesecake cool in the pan on a rack and chill it, covered, overnight. Remove the side of the pan and garnish the top of the cheesecake with the pecans.